Roller bit



Dec. 29, 1953 w. B. NOBLE 2,664,321

ROLLER BIT 7 Filed. Sept. 14, 1950 2 Sheets-Sheet l W//ey B. Nob/e INVENTOR.

A r TOR/V576 Dec. 29, 1953 w, B, NQBLE 2,664,321

ROLLER BIT Filed Sept. 1.4, 1950 2 Sheets-Sheet 2 W/ley B. Nob/e INVENTOR.

A TTOR/VEYJ Patented Dec. 29, 1953 UNITED l E -NT OFFICE ao'iZLER err Wiley B; NobleaHoiiston, Tex assigiior to -Re'll Roller Bit Companyqliouston, Tex., a corporation of Texas- This invention relates generally to roller bits for deep well drilling, and particularly to a roller bit having a new and improvedbearing for the" roller cutters thereof.-

C'cnventional roller bits-for the drilling cfoil wells include abit head-in' which are mounted roller cutters provided with teeth to penetrate theforinatioh when'the head is rotated by the usual drill stem. During drilling ol'aerations,v the bearines' cf the roller cutters are subjected to very great shocks-andstrains, including destructive end thrusts; The bearings are also subjected to the abrasive action of mud-laden fluid which is pumped downwardly throuehthe drill-stem'ancl: hit and rises upwardlyin the space between the drill-stein andthe wall of the well to keep-the cutters'co'oi, to removethe cuttings, and to'perform other functions well known to those'skilled in the art.-

The general object-of this inventionis to provitiea roller-bit with new and improved bearings.

A specificobjectoi the invention is'to provide a rolleribit with new and improvedend thrust hearing rollers.

Other objects will hereinafter appear.

The preferred embodiments of the invention are illustrated byxthe accompanying drawings in which 1 isa partly sectional elevation of a roller bit of the cone type; Fig. 2, a section: on the line 2+2 of Fig. 1; Fig. 3, a detailview ofthethrust hearing rollers and associated parts; and Fig. 4, a fragmentary sectional View illus-- trating a sidercller cutter assembly for thecon-- ventional cross roller cutter bit.

Referring to Fig. l, the bit hcadis indicatedat l and the roller cutters at 2. The head i is pro'-- vided'with a-recess in its bottom defined by up? wardly converging walls from which project downwardly inwardly annular flanges, one of which is indicated at 3,providingaracewayfor the load sustaining bearing rollers Welded as indicated at 6 inthe here i in: the head I is-a shaft 3 having-anannular flange}! anda reduced raceway. I i for any new andimproved-thrustbearing rollers 15.

The thrust bearing rollers 15- are rotatable on a-Xe'ssubstantiallyradial to the axis' of rotation of thecuttr 2.---

As sh'own indetail in Figs: 2 and-3, these rollers i5 includea tapered portion 15-41; a substantiallycylindriizzal portion i 54; and a rounded end portion iE-c. ihe tapered portion lE-a maybe deec'i'ibed as Haste-conical,- its major diameter being substantially the same as theoliameteroithe cylindrical portion 15-1); The rounded pertionlt-cmay be a spherical segment.

The 'raceway H wliich maybe referred to as a shaft raceway, has inwardly tapered sidewalls ti-ai-ahd the tapered portions lt-a of the thrust bearin'g rollers ifi bear against these'side walls i-i a The'cutter 2=is provided with a raceway le and thiscutter-raceway it has substantially parallel side walls lt-a' and a rounded bottoml-ii-b provided with an annular groove 1 the. The cylindrical portion l5-b ofthe thrust bearing roller I5'bears against the parallel side Walls Ie'a oflthe cutter raceway i6; and the rounded end iE-c of the thrust bearing roller l5 bears against the" rounded bottom l6--b of the cutter race- W337 IBM Within the shaft raceway ll is a coiled spring I? which serves to yieldably urge the thrust bearing;.rollers-IE-"outwardly into their operative positions;

The parts==iiiay be'as'ser'nbled as follows: The shaft 8 having been placed in the cutter 2; the

thrust bearing-rollers may then be inserted in spring l'i therein may l ela ed over the annular flange}; and load rollers 5, the shaft 8 entering the bore 1- and being welded-in place as indicated at 6.

It Will be; apparent from Fig; 1 that" the load on the cutter will be sustained by the bearing rollers 5 and the friction bearing it; and that the end thr list Will besllst ained by" the thrust bearing rollers it'interh'iediate the same.

flhe tapered portions IE- a of the thrust bean rollers it perform an "important function,

When an end thrust is exerted on the bearing, the tapered portions its-a, bearing against the tapered side wall I l-a of the shaft raceway I I, tend to urge the thrust rollers 55 outwardly into their operative positions. The spring I? constitutes a resilient means to urge the thrust rollers it: outwardly into, and to hold the same in, their operative positions. When the thrust rollers [5 become worn, the spring I! urges the thrust rollers outwardly and thereby compensate for wear by maintaining the thrust rollers in their outer operative positions. The bearing area between the ends i5-c of the rollers l5 and the bottom 16-2) of the cutter raceway Iii is a relatively large area because the said end and bottom are rounded. The annular groove 16-0 in the bottom of the cutter raceway i6 serves as a channel for lubricant and also as a trap for abrasive material to reduce wear on the end IE-c of the roller i5.

The diameter of the thrust roller i5 is greater than its length. This results in an acute angle between the direction in which a longitudinal thrust is exerted and the direction in which that thrust is transmitted from the cutter to the shaft through the roller 15.

As will appear in Fig. 2, the tapered surfaces iS-a bear against each other and since the thrust rollers 55 rotate on axes substantially radial to the axis of rotation of the cutter 2, the tapered portions iii-a roll upon each other and thus provide a good bearing between the thrust rollers I5.

Referring now to the side roller cutter assembly shown by Fig. 4, the cross roller bit head is indicated at 29. It is provided with a downwardly and inwardly extending flange 2! having raceways 22 for the load rollers 23. Fitting within the bore 24 of the head is a bushing 25 having an annular flange 28 and a reduced extension 27. The annular flange 26 on the bushing 25 forms with the annular flange 2| on the head a raceway 28 for my new and improved thrust bearing rollers 2Q. The numeral 36 indicates load rollers on the reduced extension 21 of the bushing 25. Extending through a bore 3| in the bushing is the side roller cutter pin 32. The pin 32 is integral with and extends upwardly and outwardly from the bridge 33.

The thrust bearing rollers 29 are the same as the thrust bearing rollers [5 shown by Figs. 1, 2 and 3 and in the raceway 28 is a coiled spring 3t which corresponds with the coiled spring I! shown by Figs. 1, 2 and 3. The side roller cutter 35 is provided with a raceway 36 which is the same as the raceway 16 shown by Figs. 1, 2 and 3.

The parts shown by Fig. 4 may be assembled as follows: The bushing 25 is placed Within the cutter 35. The load rollers 39 are placed between the reduced extension 27 of the bushing 25 and the cutter 35. The thrust bearing rollers 29 are then placed in the cutter raceway 3B and the spring as is compressed to a diameter smaller than its normal diameter and inserted within the circle of thrust bearing rollers 29. The load rollers 23 are placed on the raceway 22 and the cutter 35 is then placed over the rollers 23 and flange 2!. The pin 32 may then be inserted through the bore st in the bushing 25 and welded in place as indicated at 31.

The invention is not limited to the preferred embodiments herein disclosed. Various changes within the scope of the following claims will be apparent to those skilled in the art.

I claim:

1. A bit having a shaft; a roller cutter rotatable on said shaft; said shaft having a raceway with inwardly tapered side walls, said cutter having a raceway with substantially parallel side walls and a rounded, grooved bottom; thrust bearing rollers in said raceways, rotatable on axes substantially radial to the axis of rotation of said cutter, and having tapered inner portions to bear against each other and against the tapered side walls of said shaft raceway, a substantially cylindrical portion to engage the substantially parallel side walls of said cutter raceway, and a rounded end to engage the rounded bottom of said cutter raceway; a spring in said shaft raceway to urge said rollers outwardly into their operative positions; and load sustaining bearings on each side of said thrust bearing rollers.

2. A bit having a shaft; a roller cutter rotatable on said shaft; said shaft having a raceway with inwardly tapered side walls, said cutter having a raceway with a rounded bottom; thrust bearing rollers in said raceways, rotatable on axes substantially radial to the axis of rotation of said outer, and having tapered inner portions to bear against each other and against the tape-red side Walls of said shaft raceway, and a rounded end to engage the rounded bottom of said cutter raceway; aspring in said shaft raceway to urge said rollers outwardly into their operative positions; and load sustaining bearings on each sid of said thrust bearing rollers.

3. A bit having a shaft; a roller cutter rotatable on said shaft; said shaft having a raceway with inwardly tapered side walls, said cutter having a raceway; thrust bearing rollers in said raceways, rotatable on axes substantially radial to the axis of rotation of said cutter, and having tapered inner portions to bear against each other and against the tapered side walls of said shaft raceway; a spring in said shaft raceway to urge said rollers outwardly into their operative positions; and load sustaining bearings on each side of said thrust bearing rollers.

4. A bit having a shaft; a roller cutter rotatable on said shaft; said shaft having a raceway, said cutter having a raceway; thrust bearing rollers in said raceways and rotatable on axes substantially radial to the axis of rotation of said cutter; a spring in said shaft raceway to urge said rollers outwardly into their operative positions; and load sustaining bearings on each side of said thrust bearing rollers.

5. A bit having a shaft, a roller cutter rotatable on said shaft, said shaft and cutter having raceways, one of said raceways having tapered side walls, thrust bearing rollers in said race- Ways, said rollers being rotatable on axes substantially radial to the axis of rotation of said cutter and having tapered portions bearing against each other and against the said tapered side walls of said raceway, and yieldable means to urge said rollers into their operative positions in said raceways.

6. A bit having a shaft, a roller cutter rotatable on said shaft, said shaft and cutter having raceways, one of said raceways having tapered side walls, and thrust bearing rollers in said raceways, said rollers being rotatable on axes substantially radial to the axis of rotation of said cutter and having tapered portions bearing against each other and against the said tapered side walls of said raceway.

7. A bit having a shaft, a roller cutter rotatable on said shaft, said shaft and cutter having raceways, and thrust bearing rollers in said raceways,

said rollers being rotatable on axes substantially radial to the axis of rotation of said cutter and having tapered portions bearing against each other.

8. A bit having a shaft, a roller cutter rotatable on said shaft, raceways in said shaft and cutter, thrust bearing rollers in said raceways and rotatable on axes substantially radial to the axis of rotation of said cutter, and yieldable means to urge said rollers into their operative positions in said raceways.

9. A bit having a shaft, a roller cutter rotatable on said shaft, said shaft having a raceway with tapered side walls, said cutter having a raceway, and thrust bearing rollers in said raceways, said 6 thrust rollers being rotatable on axes substan tially radial to the axis of rotation of said cutter andhaving tapered portions bearing against each other and the said tapered side walls of said raceway.

WILEY B. NOBLE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,106,065 Vandegrift Aug. a, 191 1,760,317 Pickin May 27, 1930 2,284,427 Hufierd May 26, 1942 2,293,603 Francis Aug. 18, 1942 

